Change of Mineral Elements and Amino Acids in Malus hupehensis var. pingyiensis Leaves under Cd Treatment

摘要

The objective of this paper is to research the effects of CdCl₂ treatment on mineral elements and amino acids in leaves of Malus hupehensis var. pingyiensis. The seedlings of Malus hupehensis var. pingyiensis with 6 leaf were cultured in 1/2 Hoagland nutrient solutions of different CdCl₂ treatments (0, 0.5, 5 and 10 mg·L-1), respectively. The mineral elements and amino acids of the leaves in Malus hupehensis var. pingyiensis were measured in the day 30. Compared with the control (0 mg·L-1 CdCl₂), the treatments significantly decreased the contents of Mg, Fe and Zn in the tested leaves and obviously increased the contents of Cd in the experimental leaves. As to Ca and Mn, low concentration Cd treatment (0.5 mg·L-1 CdCl₂) promoted their absorption, however, high concentration Cd treatments (5 and 10 mg·L-1 CdCl₂) inhibited their absorption. The metabolism pathway and content of amino acids in the Malus hupehensis var. pingyiensis leaves under Cd treatment were modified, the content of amino acids in the glycolate pathway became larger than that in control, the content of amino acids in the pyruvic acid synthesis pathway and tyrosine and phenylalanine became smaller than that in control, the content of other amino acids also had made a certain degree change. The results provided the important basis for safety production and quality evaluation of leaves in Malus hupehensis var. pingyiensis.